.TH  ntpdate  1M 2009-08-21 "SunOS 5.11"  "System Administration Commands" 
.\"						     .\"  EDIT THIS FILE WITH CAUTION  (ntpdate-man.8)
.\"  
.\"  It has been AutoGen-ed  Friday August 21, 2009 at 02:23:24 AM IST
.\"  From the definitions    ntpdate.def
.\"  and the template file   agman8.tpl
.\"						     
.SH NAME					     
.B ntpdate
\- set the date and time by way of NTP
.SH SYNOPSIS					     
.B /usr/sbin/ntpdate 
.Op Fl  4 Ar no
.Op Fl  6 Ar no
.Op Fl  d Ar /usr/sbin/ntpdate
.Op Fl  D Ar level
.Op Fl  c Ar driftfile
.Op Fl  g Ar threshold-value
.Op Fl  k Ar keyfile
.Op Fl  l Ar logfile
.Op Fl  L Ar /usr/sbin/ntpdate
.Op Fl  m Ar /usr/sbin/ntpdate
.Op Fl  l Ar logfile
.Op Fl  n Ar /usr/sbin/ntpdate				
.SH DESCRIPTION
.sp
.LP
The \fBntpdate\fR utility sets the local date and time. To determine the correct time, it polls the Network Time Protocol (NTP) servers on the 		hosts given as arguments. This utility must be run as root on the local host. It obtains a number of samples from each of the servers and 		applies	the standard \fBNTP\fR clock filter and selection algorithms to select the best of these.
.sp
.LP
The reliability and precision of \fBntpdate\fR improve dramatically with a greater number of servers. While a single server may be used, better 	performance and greater resistance to inaccuracy on the part of any one server can be obtained by providing at least three or four servers, if not more.
.sp
.LP
The \fBntpdate\fR utility makes time adjustments in one of two ways. If it determines that your clock is off by more than 0.5 seconds it simply 	steps the time by calling \fBgettimeofday\fR(3C). If the error is less than 0.5 seconds, by default, it slews the clock's time with the offset, by way of a call to \fBadjtime\fR(2). The latter technique is less disruptive and more accurate when the offset is small; it works quite well when 	\fBntpdate\fR is run by \fBcron\fR every hour or two. The adjustment made in the latter case is actually 50% larger than the measured offset. This 		adjustment tends to keep a 	badly drifting clock more accurate, at some expense to stability. This tradeoff is usually advantageous. At boot 		time, however, it is usually better to 	step the time. This can be forced in all cases by specifying the \fB-b\fR option on the command line.
.sp
.LP
The \fBntpdate\fR utility declines to set the date if an \fBNTP\fR server daemon like \fBxntpd\fR(1M) is running on the same host. It can be run on a regular basis from \fBcron\fR(1M) as an alternative to running a daemon. Doing so once every one to two hours results in precise enough 		timekeeping to avoid stepping the clock.	
.SH OPTIONS
.TP 
.BR  -4 
Force DNS resolution of the given host names
.sp
Force DNS resolution of following host names on the command line to the
IPv4 namespace.
.TP 
.BR  -6 
Force DNS resolution of the given host names
.sp
Force DNS resolution of following host names on the command line to the
IPv6 namespace.
.TP 
.BR  -d 
this is used to set the debugging mode
.sp
Specify debugging mode.  This option may occur more than once,
with each occurrence indicating greater detail of display.
.TP 
.BR  -D 
specify the debugging level
.sp
when debugging mode is enabled, you may need bebuggin level to specify. this option
is there to provide that facility. 
.TP 
.BR  -c 
this option let you to specify a frequency file, if not provided default frequency file is used
.sp
Specify the name and path of the frequency file, default
/etc/ntp.drift.  This is the same operation as the driftfile
driftfile configuration command.
.TP 
.BR  -g 
this option let you to specify a threshold value 
.sp
Normally, ntpd exits with a message to the system log if the off-
set exceeds the panic threshold, which is 1000 s by default.
This option allows thetime to be set to any value without
restriction; however, this can happen only once.  If the thresh-
old is exceeded after that, ntpd will exit with a message to the
system log.  This option can be used with the -q and -x options.
See the tinker command for other options.

.TP 
.BR  -k 
this option let you to specify a symmetric key file, if not provided default key file is used
.sp
Specify the name and path of the frequency file, default
/etc/ntp.drift.  This is the same operation as the driftfile
driftfile configuration command.
.TP 
.BR  -l 
this option let you to specify the path of the log file, if not provided default system log file is used
.sp
Specify the name and path of the log file.  The default is the
system log file.  This is the same operation as the logfile
logfile configuration command.
.TP 
.BR  -L 
Tells ntpd not to listen to virtual IPs
.sp
Do not listen to virtual IPs.  The default is to listen.
.TP 
.BR  -m 
client can synchronize with multicast and broadcast servers. this option is used to set the client synchronization with multicast servers
.sp
 Enable the client to synchronize to multicast servers at the IPv4
     multicast group address 224.0.1.1.
.TP 
.BR  -l 
this option let you to specify the path of the log file, if not provided default system log file is used
.sp
Specify the name and path of the log file.  The default is the
system log file.  This is the same operation as the logfile
logfile configuration command.
.TP 
.BR  -n 
Do not fork.
.sp
Do not fork.

.SH FILES
sp
ne 2
mk
na
\fB\fB/etc/inet/ntp.keys\fR\fR
ad
RS 22n
rt
Contains the encryption keys used by \fBntpdate\fR.
RE
.SH SEE ALSO
sp
LP
\fBcron\fR(1M), \fBxntpd\fR(1M), \fBadjtime\fR(2), \fBgettimeofday\fR(3C), \fBsettimeofday\fR(3C)\fBsyslog\fR(3C), \fB attributes\fR(5)
.SH BUGS


